KR20200056286A - Photoelectric device and organic sensor and electronic device - Google Patents

Abstract

The present invention relates to a photoelectric conversion device and an organic sensor including the same, and an electronic device. The photoelectric device comprises: a first electrode and a second electrode facing each other; a photoelectric conversion layer disposed between the first electrode and the second electrode and absorbing light in at least one part of a wavelength to be converted into an electrical signal; and an inorganic nano-layer disposed between the first electrode and the photoelectric conversion layer and including a lanthanide element, calcium (Ca), potassium (K), aluminum (Al), or an alloy thereof.

Description

Photoelectric conversion elements, organic sensors, and electronic devices {PHOTOELECTRIC DEVICE AND ORGANIC SENSOR AND ELECTRONIC DEVICE}

Photoelectric conversion elements, organic sensors and electronic devices.

The photoelectric conversion element is a device that receives light and converts it into an electrical signal, and includes photodiodes and phototransistors, and may be applied to an organic sensor, a photo detector, or a solar cell.

The organic sensor requires a higher resolution as the day goes by, and accordingly, the pixel size becomes smaller. In the case of a silicon photodiode mainly used at present, since the size of the pixel decreases and the absorption area decreases, sensitivity deterioration may occur. Accordingly, organic materials that can replace silicon are being researched.

Since the organic material has a large extinction coefficient and can selectively absorb light in a specific wavelength range according to the molecular structure, it is advantageous for high integration because it can simultaneously replace a photodiode and a color filter.

However, the organic material may exhibit different properties from silicon due to high binding energy and recombination behavior, and it is difficult to accurately predict the properties of the organic material, so it is difficult to easily control the properties required in the photoelectric conversion device. .

One embodiment provides a photoelectric conversion device capable of improving charge extraction efficiency.

Another embodiment provides an organic sensor including the photoelectric conversion element.

Another embodiment provides an electronic device including the photoelectric conversion element or the organic sensor.

According to an embodiment, the first and second electrodes facing each other, the photoelectric conversion layer that is located between the first electrode and the second electrode and absorbs light in at least a portion of the wavelength region to convert it into an electrical signal, and the agent Provided is a photoelectric conversion element including an inorganic nanolayer positioned between one electrode and the photoelectric conversion layer and comprising an lanthanide element, calcium (Ca), potassium (K), aluminum (Al), or an alloy thereof.

The lanthanide element may include ytterbium (Yb).

The inorganic nano layer may be in contact with the first electrode.

One surface of the inorganic nano layer may be in contact with the first electrode, and the other surface of the inorganic nano layer may be in contact with the photoelectric conversion layer.

The first electrode may be a transparent electrode having a light transmittance of about 80% or more or a reflective electrode having a light transmittance of about 10% or less.

 The transparent electrode may include at least one of an oxide conductor and a carbon conductor.

The thickness of the inorganic nano layer may be less than about 5nm.

The thickness of the inorganic nano layer may be less than about 2nm.

The first electrode may be a cathode and the second electrode may be an anode.

According to another embodiment, a first electrode including a transparent conductor having a light transmittance of 80% or more or a reflective conductor having a light transmittance of less than 10%, located on the first electrode, absorbs light in at least a portion of a wavelength region and converts it into an electrical signal The photoelectric conversion layer, and a second electrode located on the photoelectric conversion layer, the surface of the first electrode facing the photoelectric conversion layer is covered with an inorganic nano layer having a thickness of 5 nm or less, and the photoelectric conversion layer and An effective work function at the surface of the opposing first electrode provides a photoelectric conversion element smaller than the work function of the transparent conductor or the reflective conductor.

The difference between the work function of the transparent conductor or the reflective conductor and the effective work function on the surface of the first electrode facing the photoelectric conversion layer may be about 0.5 eV or more.

The work function of the transparent conductor or the reflective conductor may be about 4.5 eV or more, and an effective work function at the surface of the first electrode facing the photoelectric conversion layer may be about 4.0 eV or less.

The effective work function at the surface of the first electrode facing the photoelectric conversion layer may be about 3.0 eV or less.

The inorganic nano-layer may include an inorganic material, and the inorganic material may include a lanthanide element, calcium (Ca), potassium (K), aluminum (Al), or alloys thereof.

The lanthanide element may include ytterbium (Yb).

The transparent electrode may include an oxide conductor or a carbon conductor.

The inorganic nano layer may have a thickness of about 2 nm or less.

The first electrode may be a cathode and the second electrode may be an anode.

According to another embodiment, an electronic device including the photoelectric conversion element is provided.

According to another embodiment, an organic sensor including the photoelectric conversion element is provided.

According to another embodiment, an electronic device including the organic sensor is provided.

By improving the charge mobility and reducing the residual charge, it is possible to increase the charge extraction efficiency of the photoelectric conversion element.

1 is a cross-sectional view showing a photoelectric conversion device according to an embodiment,
2 is a cross-sectional view showing a photoelectric conversion device according to another embodiment.
3 is a cross-sectional view schematically showing an example of an organic CMOS image sensor according to an embodiment,
4 is a cross-sectional view schematically showing another example of an organic CMOS image sensor according to another embodiment,
5 is a plan view schematically showing an organic CMOS image sensor according to an embodiment,
6 is a cross-sectional view showing an example of the organic CMOS image sensor of FIG. 5,
7 is a cross-sectional view showing another example of the organic CMOS image sensor of FIG. 5,
8 is a cross-sectional view showing another example of the organic CMOS image sensor of FIG. 5,
9 is a cross-sectional view showing another example of the organic CMOS image sensor of FIG. 5,
10 is a plan view schematically showing an organic CMOS image sensor according to another embodiment,
11 is a cross-sectional view of the organic CMOS image sensor of FIG. 10,
12 is a cross-sectional view showing another example of the organic CMOS image sensor of FIG. 10,
13 is a plan view schematically showing an organic CMOS image sensor according to an embodiment,
14 is a cross-sectional view showing an example of the organic CMOS image sensor of FIG. 13,
15 is a cross-sectional view showing an example of an organic CMOS image sensor,
16 is a cross-sectional view showing an example of an organic CMOS image sensor,
17 is a schematic diagram of an electronic device according to an embodiment.

Hereinafter, embodiments will be described in detail so that those skilled in the art can easily implement them. However, the actual applied structure may be implemented in various different forms and is not limited to the implementations described herein.

In the drawings, the thickness is enlarged to clearly express the various layers and regions.

When a portion of a layer, film, region, plate, etc. is said to be “above” another portion, this includes not only the case “directly above” the other portion but also another portion in the middle. Conversely, when one part is "just above" another part, it means that there is no other part in the middle.

In the following, unless otherwise defined, 'substituted' means that the hydrogen atom in the compound is a halogen atom, a hydroxy group, an alkoxy group, a nitro group, a cyano group, an amino group, an azido group, an amidino group, a hydrazino group, a hydrazono group, Carbonyl group, carbamyl group, thiol group, ester group, carboxyl group or salt thereof, sulfonic acid group or salt thereof, phosphoric acid or salt thereof, silyl group, C1 to C20 alkyl group, C2 to C20 alkenyl group, C2 to C20 alkynyl group, C6 to C30 Aryl group, C7 to C30 arylalkyl group, C1 to C30 alkoxy group, C1 to C20 heteroalkyl group, C3 to C20 heteroaryl group, C3 to C20 heteroarylalkyl group, C3 to C30 cycloalkyl group, C3 to C15 cycloalkenyl group, C6 to It means substituted with a substituent selected from C15 cycloalkynyl group, C3 to C30 heterocycloalkyl group, and combinations thereof.

In the following, unless otherwise defined, 'hetero' means one to four heteroatoms selected from N, O, S, Se, Te, Si and P.

In the following, 'combination' includes mixed and two or more laminated structures.

In the following, 'metal' includes metal, semimetal, or combinations thereof.

Hereinafter, the 'energy level' is the highest occupied molecular orbital (HOMO) energy level or the lowest unoccupied molecular orbital (LUMO) energy level.

Hereinafter, the value of the work function or energy level is expressed as an absolute value from a vacuum level. In addition, a deep, high or large work function or energy level means a large absolute value with a vacuum level of '0eV', and a low, low or small work function or energy level with a vacuum level of '0eV'. It means that the absolute value is small.

Hereinafter, a photoelectric conversion device according to an embodiment will be described.

1 is a cross-sectional view showing a photoelectric conversion device according to an embodiment.

Referring to FIG. 1, the photoelectric conversion element 100 according to an embodiment includes a first electrode 10, a second electrode 20, a photoelectric conversion layer 30 and an inorganic nano layer 40.

The substrate (not shown) may be disposed on the first electrode 10 side or may be disposed on the second electrode 20 side. The substrate may be made of, for example, an inorganic material such as glass, polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polyamide, polyethersulfone or a combination thereof, or a silicon wafer or the like. The substrate can be omitted.

The first electrode 10 and the second electrode 20 face each other. One of the first electrode 10 and the second electrode 20 is an anode, and the other is a cathode. For example, the first electrode 10 may be a cathode and the second electrode 20 may be an anode. For example, the first electrode 10 may be an anode and the second electrode 20 may be a cathode.

At least one of the first electrode 10 and the second electrode 20 may be a transparent electrode. Here, the transparent electrode may be a transparent electrode having a high transmittance of about 80% or more of light transmittance, and may not include a translucent electrode for microcavity, for example. The transparent electrode may include, for example, at least one of an oxide conductor and a carbon conductor, and the oxide conductor may be, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide. (zinc tin oxide, ZTO), aluminum tin oxide (AlTO) and aluminum zinc oxide (Aluminum zinc oxide, AZO) may be at least one selected from, and the carbon conductor may be at least one selected from graphene and carbon nanoparticles. have.

One of the first electrode 10 and the second electrode 20 may be a reflective electrode. Here, the reflective electrode may be, for example, a reflective electrode having a light transmittance of less than about 10% or a high reflectance of about 5% or more. The reflective electrode may include a reflective conductor such as metal, for example, aluminum (Al), silver (Ag), gold (Au), or alloys thereof.

For example, the first electrode 10 may be a transparent electrode having a light transmittance of 80% or more or a reflective electrode having a light transmittance of less than about 10%.

The photoelectric conversion layer 30 is positioned between the first electrode 10 and the second electrode 20. The photoelectric conversion layer 30 may absorb at least a portion of the wavelength region and convert it into an electrical signal, for example, light in the green wavelength region (hereinafter referred to as “green light”), light in the blue wavelength region (hereinafter “blue light”). It can convert some of the light in the red wavelength region (hereinafter referred to as 'red light') and the light in the infrared wavelength region (hereinafter referred to as 'infrared light') into electrical signals.

For example, the photoelectric conversion layer 30 may selectively absorb any one of green light, blue light, red light, and infrared light. Here, selectively absorbing any one of green light, blue light, red light, and infrared light has a peak absorption wavelength (λ _max ) of an absorption spectrum of about 500 to 600 nm, about 380 nm or more and less than 500 nm, about 600 nm or more and 700 nm or less and about It means that it exists in any one of 700 nm or more and 3000 nm or less, and the absorption spectrum in the corresponding wavelength region is significantly higher than the absorption spectrum in other wavelength regions. Remarkably high here means that the area of the absorption spectrum in the corresponding wavelength region is about 70% or more, about 75% or more, about 80% or more, about 85% or more, about 90% or more, about 95% or more with respect to the total area of the absorption spectrum, It means about 98% or more, about 99% or more, or about 100%.

In the photoelectric conversion layer 30, at least one p-type semiconductor and at least one n-type semiconductor may form a pn junction, and generate excitons after receiving light from the outside to generate excitons. It can be separated into holes and electrons.

Each of the p-type semiconductor and the n-type semiconductor may be a light absorbing material, for example, at least one of the p-type semiconductor and the n-type semiconductor may be an organic light absorbing material. For example, at least one of the p-type semiconductor and the n-type semiconductor may be a wavelength selective absorbing material that selectively absorbs light in a predetermined wavelength range, for example, at least one of the p-type semiconductor and the n-type semiconductor is a wavelength selective organic absorbing material Can be. The p-type semiconductor and the n-type semiconductor may have peak absorption wavelengths (λ _max ) in the same or different wavelength regions.

For example, the p-type semiconductor may be an organic material having a core structure including an electron donating moiety, a pi conjugated connector, and an electron accepting moiety.

The p-type semiconductor may be represented by, for example, Formula 1 below, but is not limited thereto.

[Formula 1]

EDG-HA-EAG

In Chemical Formula 1,

HA may be a C2 to C30 heterocyclic group having at least one of O, S, Se, Te and Si,

EDG may be an electron donating moiety,

The EAG can be an electron accepting moiety.

For example, the p-type semiconductor represented by Chemical Formula 1 may be represented by the following Chemical Formula 1A, for example.

[Formula 1A]

In Formula 1A,

X may be O, S, Se, Te, SO, SO ₂ or SiR ^a R ^b ,

Ar may be a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted C3 to C30 heterocyclic group, or two or more fused rings selected from them,

Ar ^1a and Ar ^2a may be each independently a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted C3 to C30 heteroaryl group,

Ar ^1a and Ar ^2a may each independently exist or may combine with each other to form a fused ring,

R ^1a to R ^3a , R ^a and R ^b are each independently hydrogen, deuterium, substituted or unsubstituted C1 to C30 alkyl group, substituted or unsubstituted C6 to C30 aryl group, substituted or unsubstituted C3 to C30 heteroaryl Group, a substituted or unsubstituted C1 to C6 alkoxy group, a halogen or a cyano group.

For example, in Formula 1A, Ar ^1a and Ar ^2a are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenanthrenyl group, and a substitution. Or an unsubstituted pyridinyl group, a substituted or unsubstituted pyridazinyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrrazinyl group, a substituted Or an unsubstituted quinolinyl group, a substituted or unsubstituted isoquinolinyl group, a substituted or unsubstituted naphthyridinyl group, or a substituted or unsubstituted cinolinyl group Group, substituted or unsubstituted quinazolinyl group, substituted or unsubstituted phthalazinyl group, substituted or unsubstituted benzotriazinyl group, substituted or unsubstituted pyridopyrazinyl (pyridopyrazinyl) group, a substituted or unsubstituted pyridopyrimidinyl group, and a substituted or unsubstituted pyridopyridazinyl group (pyridopyridazinyl) group.

For example, Ar ^1a and Ar ^2a of Formula 1A may be fused to each other to form a ring, and Ar ^1a and Ar ^2a may be, for example, a single bond,-(CR ^g R ^h ) _n2- (n2 is 1 or 2),- O-, -S-, -Se-, -N =, -NR ^i- , -SiR ^j R ^k -and -GeR ^l R ^m -may be connected to one selected to form a ring. Wherein R ^g to R ^m are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 heteroaryl group, a substituted or unsubstituted It may be a C1 to C6 alkoxy group, halogen or cyano group.

For example, the p-type semiconductor represented by Chemical Formula 1 may be represented by the following Chemical Formulas 1B-1 or 1B-2.

[Formula 1B-1] [Formula 1B-2]

In Formula 1B-1 or 1B-2,

X ¹ may be Se, Te, O, S, SO or SO ₂ ,

Ar ³ may be a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted C3 to C30 heterocyclic group, or two or more fused rings selected from the above,

R ¹ to R ³ are each independently hydrogen, deuterium, substituted or unsubstituted C1 to C30 alkyl group, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C6 to C30 aryl group, substituted or unsubstituted C3 to C30 heteroaryl group, halogen, cyano group, cyano-containing group and combinations thereof,

G is a single bond, -O-, -S-, -Se-, -N =,-(CR ^f R ^g ) _k- , -NR ^h- , -SiR ⁱ R ^j- , -GeR ^k R ^l- , -(C (R ^m ) = C (R ⁿ ))-and SnR ^o R ^p , where R ^f , R ^g , R ^h , R ⁱ , R ^j , R ^k , R ^l , R ^m , R ⁿ , R ^o and R ^p can each independently be selected from hydrogen, halogen, substituted or unsubstituted C1 to C10 alkyl groups, substituted or unsubstituted C1 to C10 alkoxy groups and substituted or unsubstituted C6 to C12 aryl groups. And R ^f and R ^g , R ⁱ and R ^j , R ^k and R ^l , R ^m and R ⁿ and R ^o and R ^p may each independently exist or be connected to each other to form a ring, and k is 1 Or 2

Y ² can be selected from O, S, Se, Te and C (R ^q ) (CN) (where R ^q is selected from hydrogen, cyano group (-CN) and C1 to C10 alkyl group),

R ^6a to R ^6d . R ^7a to R ^7d , R ¹⁶ and R ¹⁷ are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 heteroaryl group, Halogen, cyano group, cyano-containing group, and combinations thereof,

R ^6a to R ^6d may exist independently or two adjacent to each other may be connected to each other to form a fused ring,

R ^7a to R ^7d may each independently exist or two adjacent to each other may be connected to each other to form a fused ring.

For example, Ar ³ of Formula 1B-1 or 1B-2 may be benzene, naphthylene, anthracene, thiophene, selenophene, tellurofen, pyridine, pyrimidine, or two or more fused rings selected from them.

The n-type semiconductor may be, for example, fullerene or a fullerene derivative, but is not limited thereto.

The photoelectric conversion layer 30 may be an intrinsic layer (I layer) in which a p-type semiconductor and an n-type semiconductor are mixed in a bulk heterojunction form. At this time, the p-type semiconductor and the n-type semiconductor may be mixed at a volume ratio of about 1: 9 to 9: 1, and within the above range, for example, at a volume ratio of about 2: 8 to 8: 2, and within the above range For example, it may be mixed in a volume ratio of about 3: 7 to 7: 3, within this range, for example, in a volume ratio of about 4: 6 to 6: 4, within this range, for example, in a volume ratio of about 5: 5 Can be mixed.

The photoelectric conversion layer 30 may include a p-type layer including the above-described p-type semiconductor and a double layer including an n-type layer including the above-described n-type semiconductor. At this time, the thickness ratio of the p-type layer and the n-type layer may be about 1: 9 to 9: 1, and within the above range, for example, about 2: 8 to 8: 2, about 3: 7 to 7: 3, and about 4: 6 to 6: 4 or about 5: 5.

 The photoelectric conversion layer 30 may further include a p-type layer and / or an n-type layer in addition to the intrinsic layer. The p-type layer may include the p-type semiconductor described above, and the n-type layer may include the n-type semiconductor described above. For example, it may be included in various combinations such as p-type layer / I layer, I-layer / n-type layer, and p-type layer / I-layer / n-type layer.

The inorganic nano layer 40 may be positioned between the first electrode 10 and the photoelectric conversion layer 30 and may be in contact with, for example, the first electrode 10. For example, one surface of the inorganic nano layer 40 may be in contact with the first electrode 10 and the other surface of the inorganic nano layer 40 may be in contact with the photoelectric conversion layer 30.

The inorganic nano layer 40 may be a very thin thin film having a thickness of several nanometers, and may have a thickness of, for example, about 5 nm or less, for example, about 3 nm or less, for example, about 2 nm or less. The inorganic nano layer 40 may have, for example, a thickness of about 1 nm to 5 nm, about 1 nm to 3 nm, and about 1 nm to 2 nm.

The inorganic nano layer 40 may include an inorganic material having a lower work function than the first electrode 10. For example, the work function of the inorganic nano layer 40 may be less than about 0.5 eV than the work function of the first electrode 10. For example, the work function of the first electrode 10 may be about 4.5 eV or more, and the work function of the inorganic nano layer 40 may be about 4.0 eV or less. For example, the work function of the first electrode 10 may be about 4.5 eV or more, and the work function of the inorganic nano layer 40 may be about 3.5 eV or less. For example, the work function of the first electrode 10 may be about 4.5 eV or more, and the work function of the inorganic nano layer 40 may be about 3.0 eV or less. For example, the work function of the first electrode 10 may be about 4.5 eV or more, and the work function of the inorganic nano layer 40 may be about 2.8 eV or less. For example, the work function of the first electrode 10 may be about 4.5 eV to 5.0 eV, and the work function of the inorganic nano layer 40 may be about 1.5 eV to 4.0 eV, about 1.5 eV to 3.5 eV, about 1.5 eV to 3.0 eV. , About 1.5eV to 2.8eV.

Meanwhile, the inorganic nano layer 40 may be made of a material that satisfies the above-described work function and can be formed by thermal evaporation. As described above, the inorganic nano layer 40 is formed by thermal evaporation, thereby preventing the photoelectric conversion layer 30 from being thermally and physically damaged in the step of forming the inorganic nano layer 40 and / or subsequent processes. ) Can prevent performance degradation due to deterioration.

Inorganic materials capable of satisfying these characteristics may include, for example, lanthanide elements, calcium (Ca), potassium (K), aluminum (Al), or alloys thereof. The lanthanide element may include, for example, ytterbium (Yb).

As described above, the inorganic nano layer 40 is in contact with the surface of the first electrode 10 between the first electrode 10 and the photoelectric conversion layer 30 and has a very thin thickness compared to the first electrode 10. Can have Accordingly, the inorganic nano layer 40 may function as the surface treatment layer of the first electrode 10 on the surface of the first electrode 10 facing the photoelectric conversion layer 30, for example, the photoelectric conversion layer ( 30) may serve to control an effective work function of the first electrode 10 at the surface of the first electrode 10 facing. Here, the effective work function may be a work function at the interface of two layers in a structure in which two layers having different electrical properties abut. The effective work function of the first electrode 10 at the interface between the first electrode 10 and the photoelectric conversion layer 30 can be controlled by the very thin inorganic nano layer 40 described above, for example, the first It may be a composite work function of the electrode 10 and the inorganic nano-layer 40.

For example, the effective work function at the surface of the first electrode 10 facing the photoelectric conversion layer 30 is a transparent conductor or a reflective conductor forming the first electrode 10 under the influence of the inorganic nano layer 40. The work function of the sieve may be different, for example, the effective work function at the surface of the first electrode 10 facing the photoelectric conversion layer 30 is the work of the transparent conductor or the reflective conductor constituting the first electrode 10 It can be smaller than a function. For example, the effective work function at the surface of the first electrode 10 facing the photoelectric conversion layer 30 is the same as the work function of the inorganic nano layer 40 or the work function of the inorganic nano layer 40 and the first electrode ( It can be the middle value of the work function of 10).

For example, the difference between the work function of the transparent conductor or the reflective conductor constituting the first electrode 10 and the effective work function at the surface of the first electrode 10 facing the photoelectric conversion layer 30 is about 0.5 eV. It may be abnormal. For example, the work function of the transparent conductor or the reflective conductor constituting the first electrode 10 may be about 4.5 eV or more, and the effective work function at the surface of the first electrode 10 may be about 4.0 eV or less. For example, the work function of the transparent conductor or the reflective conductor constituting the first electrode 10 may be about 4.5 eV or more, and the effective work function at the surface of the first electrode 10 may be about 3.5 eV or less. For example, the work function of the transparent conductor or the reflective conductor constituting the first electrode 10 may be about 4.5 eV or more, and the effective work function at the surface of the first electrode 10 may be about 3.0 eV or less. For example, the work function of the transparent conductor or the reflective conductor constituting the first electrode 10 may be about 4.5 eV or more, and the effective work function at the surface of the first electrode 10 may be about 2.8 eV or less. For example, the work function of the transparent conductor or the reflective conductor constituting the first electrode 10 may be about 4.5 eV to 5.0 eV, and the effective work function at the surface of the first electrode 10 is about 1.5 eV to 4.0 eV, It may be about 1.5eV to 3.5eV, about 1.5eV to 3.0eV, about 1.5eV to 2.8eV.

In this way, by lowering the work function at the surface of the first electrode 10 facing the photoelectric conversion layer 30, extraction of charges (eg electrons) moving from the photoelectric conversion layer 30 to the first electrode 10 is reduced. It is easy to reduce residual charge carriers and exhibit high charge extraction efficiency.

The photoelectric conversion element 100 may further include an anti-reflection layer (not shown) on one surface of the first electrode 10 or the second electrode 20. The anti-reflection layer is disposed on the side where the light is incident, and the light absorption can be further improved by lowering the reflectivity of the incident light. For example, when light is incident on the first electrode 10 side, the anti-reflection layer may be located on one surface of the first electrode 10, and when light is incident on the second electrode 20 side, the anti-reflection layer is the second electrode 20 It can be located on one side.

The anti-reflection layer may include, for example, a material having a refractive index of about 1.6 to 2.5, for example, at least one of metal oxides, metal sulfides, and organic materials having a refractive index in the above range. The antireflection layer is, for example, aluminum-containing oxide, molybdenum-containing oxide, tungsten-containing oxide, vanadium-containing oxide, rhenium-containing oxide, niobium-containing oxide, tantalum-containing oxide, titanium-containing oxide, nickel-containing oxide, copper-containing oxide, cobalt-containing oxide, manganese-containing Metal oxides such as oxides, chromium-containing oxides, tellurium-containing oxides, or combinations thereof; Metal sulfides such as zinc sulfide; Or it may include an organic material such as an amine derivative, but is not limited thereto.

The photoelectric conversion element 100 may generate excitons therein when light is incident from the first electrode 10 or the second electrode 20 side and the photoelectric conversion layer 30 absorbs light in a predetermined wavelength range. Excitons are separated into holes and electrons in the photoelectric conversion layer 30, and the separated holes move to the anode side, which is one of the first electrode 10 and the second electrode 20, and the separated electrons are the first electrode 10 And the second electrode 20 is moved to the other side of the cathode, the current can flow.

Hereinafter, a photoelectric conversion device according to another embodiment will be described.

2 is a cross-sectional view showing a photoelectric conversion device according to another embodiment.

Referring to FIG. 2, the photoelectric conversion element 200 according to the present embodiment is the first electrode 10, the second electrode 20, the photoelectric conversion layer 30 and the inorganic nano layer ( 40).

However, the photoelectric conversion element 200 according to this embodiment, unlike the above-described embodiment, further includes a charge auxiliary layer 45 between the second electrode 20 and the photoelectric conversion layer 30. The charge auxiliary layer 45 can facilitate the movement of charges (eg, holes) separated from the photoelectric conversion layer 30 to increase efficiency.

The charge assist layer 45 may include, for example, organic materials, inorganic materials, or organic materials. The organic material may be an organic compound having hole or electronic properties, and the inorganic material may be, for example, a metal oxide such as molybdenum oxide, tungsten oxide, or nickel oxide.

The charge assist layer 45 may include, for example, a visible light non-absorbing material that does not substantially absorb light in the visible light region, for example, a visible light non-absorbing organic material.

For example, the visible light non-absorbing material may be a compound represented by the following Chemical Formula 2A or 2B, but is not limited thereto.

 [Formula 2A]

[Formula 2B]

In Formula 2A or 2B,

M ¹ and M ² are each independently CR ⁿ R ^o , SiR ^p R ^q , NR ^r , O, S, Se or Te,

Ar ^1b , Ar ^2b , Ar ^3b and Ar ^4b are each independently a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted C3 to C30 heteroaryl group,

G ² and G ³ are each independently a single ^{bond, - (CR s R t)} n3 -, -O-, -S-, -Se-, -N =, -NR u -, -SiR v R w - or -GeR ^x R ^y -where n3 is 1 or 2,

R ³⁰ to R ³⁷ and R ⁿ to R ^y are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 heterocyclic group, It is a substituted or unsubstituted C1 to C6 alkoxy group, halogen or cyano group.

For example, the visible light non-absorbing material may be a compound represented by the following Chemical Formula 2A-1 or 2B-1, but is not limited thereto.

[Formula 2A-1]

[Formula 2B-1]

In Formula 2A-1 or 2B-1,

M ¹ , M ² , G ² , G ³ , R ³⁰ to R ³⁷ are as described above,

R ³⁸ to R ⁴⁵ are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 heteroaryl group, a substituted or unsubstituted C1 To C6 alkoxy group, halogen or cyano group.

For example, the visible light non-absorbing material may be a compound represented by the following Chemical Formula 2A-1a or 2B-1a, but is not limited thereto.

[Formula 2A-1a]

[Formula 2B-1a]

In the above formulas 2A-1a or 2B-1a, R ³⁸ to R ⁴⁵ and R ^o and R ⁿ are as described above.

The photoelectric conversion elements 100 and 200 described above may be applied to various electronic devices, and may be applied to, for example, solar cells, organic sensors, photo detectors, and photo sensors, but is not limited thereto.

The photoelectric conversion elements 100 and 200 may be applied to, for example, an organic sensor, and may be applied to, for example, an image sensor that is an example of an organic sensor.

Hereinafter, an example of the image sensor to which the above-described photoelectric conversion element is applied will be described with reference to the drawings. Here, an organic CMOS image sensor will be described as an example of the image sensor.

3 is a cross-sectional view schematically showing an example of an organic CMOS image sensor according to an embodiment.

Referring to FIG. 3, an image sensor 300 according to an embodiment includes a semiconductor substrate 110, an insulating layer 80, a photoelectric conversion element 100, and a color filter layer 70.

The semiconductor substrate 110 may be a silicon substrate, and a transfer transistor (not shown) and a charge storage 55 are integrated. The transfer transistor and / or charge storage 55 may be integrated for each pixel. The charge storage 55 is electrically connected to the photoelectric conversion element 100.

A metal wiring (not shown) and a pad (not shown) are also formed on the semiconductor substrate 110. The metal wiring and pad may be made of a metal having low specific resistance to reduce signal delay, such as aluminum (Al), copper (Cu), silver (Ag), and alloys thereof, but is not limited thereto.

An insulating layer 80 is formed on the metal wiring and the pad. The insulating layer 80 may be made of an inorganic insulating material such as silicon oxide and / or silicon nitride or a low dielectric constant (low K) material such as SiC, SiCOH, SiCO and SiOF. The insulating layer 80 has a trench 85 exposing the charge reservoir 55. Trench 85 may be filled with a filler.

The photoelectric conversion element 100 described above is formed on the insulating layer 80. The photoelectric conversion element 100 includes a first electrode 10, a second electrode 20, a photoelectric conversion layer 30 and an inorganic nano layer 40 as described above. The second electrode 20 may be a light-receiving electrode, and the first electrode 10 may be connected to the charge storage 55.

In FIG. 3, the photoelectric conversion element 100 illustrated in FIG. 1 is illustrated, but the photoelectric conversion element 200 illustrated in FIG. 2 may be equally applied. The description of the photoelectric conversion elements 100 and 200 is as described above.

A color filter layer 70 is formed on the photoelectric conversion element 100. The color filter layer 70 includes a blue filter 70a formed in a blue pixel, a red filter 70b formed in a red pixel, and a green filter 70c formed in a green pixel. However, the present invention is not limited thereto, and includes a cyan filter, a magenta filter, and / or a yellow filter in place of at least one of the blue filter 70a, the red filter 70b, and the green filter 70c, or the blue filter 70a, the red filter ( 70b) and the green filter 70c may be further included.

An insulating film (not shown) may be additionally formed between the photoelectric conversion element 100 and the color filter layer 70.

A condenser lens (not shown) may be further formed on the color filter layer 70. The condenser lens can control the direction of incident light to collect light into a single point. The condenser lens may be, for example, a cylinder shape or a hemispherical shape, but is not limited thereto.

4 is a cross-sectional view schematically showing another example of an organic CMOS image sensor according to another embodiment.

Referring to FIG. 4, the image sensor 400 according to one embodiment, as in the above-described embodiment, includes a semiconductor substrate 110, an insulating layer 80, a photoelectric conversion element 100 and a color filter layer 70. Includes. The detailed description is as described above.

However, in the image sensor 400 according to the present embodiment, unlike the above-described embodiment, the positions of the first electrode 10 and the second electrode 20 are changed. That is, the first electrode 10 may be a light receiving electrode, and the second electrode 20 may be connected to the charge storage 55.

In FIG. 4, the structure in which the photoelectric conversion element 100 of FIG. 1 is stacked is illustrated as an example, but the structure in which the photoelectric conversion element 200 of FIG. 2 is stacked may also be applied. The description of the photoelectric conversion elements 100 and 200 is as described above.

5 is a plan view schematically showing an organic CMOS image sensor according to an embodiment, and FIG. 6 is a cross-sectional view showing an example of the organic CMOS image sensor of FIG. 5.

5 and 6, an image sensor 500 according to an embodiment includes a semiconductor substrate 110 in which photo sensing elements 50a and 50b, a transfer transistor (not shown), and a charge storage 55 are integrated. ), The lower insulating layer 60, the color filter layer 70, the upper insulating layer 80 and the photoelectric conversion element 100 described above.

The semiconductor substrate 110 may be a silicon substrate, and the photosensitive elements 50a and 50b, a transfer transistor (not shown), and a charge storage 55 are integrated. The photo-sensing elements 50a and 50b may be photodiodes.

The photo-sensing elements 50a, 50b, the transfer transistor, and / or the charge storage 55 may be integrated for each pixel. For example, as shown in the drawing, the photo-sensing elements 50a, 50b include blue pixels and red pixels. And charge storage 55 may be included in the green pixel.

The photo-sensing elements 50a and 50b sense light and the sensed information may be transmitted by a transfer transistor, and the charge storage 55 is electrically connected to the first electrode 10 of the photoelectric conversion element 100 And the information in charge storage 55 can be transferred by a transfer transistor.

A metal wiring (not shown) and a pad (not shown) are also formed on the semiconductor substrate 110. The metal wiring and pad may be made of a metal having low specific resistance to reduce signal delay, such as aluminum (Al), copper (Cu), silver (Ag), and alloys thereof, but is not limited thereto. However, it is not limited to the above structure, and the metal wiring and the pad may be located under the photo sensing elements 50a and 50b.

The lower insulating layer 60 is formed on the metal wiring and the pad. The lower insulating layer 60 may be made of an inorganic insulating material such as silicon oxide and / or silicon nitride or a low dielectric constant (low K) material such as SiC, SiCOH, SiCO and SiOF. The lower insulating layer 60 has a trench 85 exposing the charge reservoir 55. Trench 85 may be filled with a filler.

A color filter layer 70 is formed on the lower insulating layer 60. The color filter layer 70 includes a blue filter 70a formed in a blue pixel and a red filter 70b formed in a red pixel. In this embodiment, an example in which a green filter is not provided is described, but in some cases, a green filter may be provided. Also, a cyan filter, a magenta filter, and / or a yellow filter may be included in place of the blue filter 70a and / or the red filter 70b, or may be further included in the blue filter 70a and the red filter 70b.

The upper insulating layer 80 is formed on the color filter layer 70. The upper insulating layer 80 removes and flattens the step by the color filter layer 70. The upper insulating layer 80 and the lower insulating layer 60 have a contact hole (not shown) exposing the pad and a trench 85 exposing the charge storage 55 of the green pixel.

The photoelectric conversion element 100 described above is formed on the upper insulating layer 80. The photoelectric conversion element 100 includes a first electrode 10, a second electrode 20, a photoelectric conversion layer 30 and an inorganic nano layer 40 as described above. The second electrode 20 may be a light receiving electrode, and the first electrode 10 may be connected to the charge storage 55.

In FIG. 6, the structure in which the photoelectric conversion element 100 of FIG. 1 is stacked is illustrated as an example, but the structure in which the photoelectric conversion element 200 of FIG. 2 is stacked may also be applied. The description of the photoelectric conversion elements 100 and 200 is as described above.

A condenser lens (not shown) may be further formed on the photoelectric conversion element 100. The condenser lens can control the direction of incident light to collect light into a single point. The condenser lens may be, for example, a cylinder shape or a hemisphere shape, but is not limited thereto.

7 is a cross-sectional view showing another example of the organic CMOS image sensor of FIG. 5.

Referring to FIG. 7, the image sensor 600 according to the present embodiment is a semiconductor in which the light sensing elements 50a and 50b, the transfer transistor (not shown), and the charge storage 55 are integrated as in the above-described embodiment It includes a substrate 110, a lower insulating layer 60, a color filter layer 70, an upper insulating layer 80 and a photoelectric conversion element 100.

However, in the image sensor 600 according to the present embodiment, the positions of the first electrode 10 and the second electrode 20 are changed unlike the above-described embodiment. That is, the first electrode 10 may be a light receiving electrode, and the second electrode 20 may be connected to the charge storage 55.

In FIG. 7, the structure in which the photoelectric conversion elements 100 of FIG. 1 are stacked is exemplarily illustrated, but the structure in which the photoelectric conversion elements 200 of FIG. 2 are stacked can also be applied.

8 is a cross-sectional view illustrating another example of the organic CMOS image sensor of FIG. 5.

The image sensor 700 according to the present embodiment is similar to the above-described embodiment, the semiconductor substrate 110, the trench in which the light sensing elements 50a, 50b, the transfer transistor (not shown) and the charge storage 55 are integrated. And an upper insulating layer 80 having 85 and a photoelectric conversion element 100.

However, in the image sensor 700 according to the present embodiment, unlike the above-described embodiment, the light sensing elements 50a and 50b are stacked in the vertical direction, and the color filter layer 70 is omitted. The photo-sensing elements 50a and 50b are electrically connected to a charge storage (not shown) and can be transferred by a transfer transistor. The light sensing elements 50a and 50b may selectively absorb light in each wavelength region according to the stacking depth.

In FIG. 8, the structure in which the photoelectric conversion elements 100 of FIG. 1 are stacked is illustrated as an example, but the structure in which the photoelectric conversion elements 200 of FIG. 2 are stacked can be applied in the same way.

9 is a cross-sectional view showing another example of the organic CMOS image sensor of FIG. 5.

Referring to FIG. 9, the image sensor 800 according to the present embodiment is a semiconductor in which the light sensing elements 50a and 50b, the transfer transistor (not shown), and the charge storage 55 are integrated as in the above-described embodiment It includes a substrate 110, an upper insulating layer 80 having a trench 85, and a photoelectric conversion element 100. However, in the image sensor 800 according to the present embodiment, unlike the above-described embodiment, the positions of the first electrode 10 and the second electrode 20 are changed. That is, the first electrode 10 may be a light receiving electrode, and the second electrode 20 may be connected to the charge storage 55.

In FIG. 9, the structure in which the photoelectric conversion elements 100 of FIG. 1 are stacked is illustrated as an example, but the structure in which the photoelectric conversion elements 200 of FIG. 2 are stacked may also be applied.

10 is a plan view schematically showing an organic CMOS image sensor according to another embodiment, and FIG. 11 is a cross-sectional view showing an example of the organic CMOS image sensor of FIG. 10.

The organic CMOS image sensor 900 according to the present embodiment selectively selects a green photoelectric conversion element that selectively absorbs light in the green wavelength region, a blue photoelectric conversion element that selectively absorbs light in the blue wavelength region, and light in the red wavelength region. It is a structure in which a red photoelectric conversion element absorbing is stacked.

The organic CMOS image sensor 900 according to the present embodiment includes a semiconductor substrate 110, a lower insulating layer 60, an intermediate insulating layer 65, an upper insulating layer 80, a first photoelectric conversion element 100a, and It includes a second photoelectric conversion element (100b) and a third photoelectric conversion element (100c).

The semiconductor substrate 110 may be a silicon substrate, and transfer transistors (not shown) and charge storages 55a, 55b, and 55c are integrated.

A metal wiring (not shown) and a pad (not shown) are formed on the semiconductor substrate 110, and a lower insulating layer 60 is formed on the metal wiring and the pad.

The first photoelectric conversion element 100a is formed on the lower insulating layer 60.

The first photoelectric conversion element 100a includes a first electrode 10a and a second electrode 20a facing each other, a photoelectric conversion layer 30a positioned between the first electrode 10a and the second electrode 20a, and It includes an inorganic nano-layer (40a). The first electrode 10a, the second electrode 20a, the photoelectric conversion layer 30 and the inorganic nano layer 40a are as described above, and the photoelectric conversion layer 30a is one of red, blue, and green. Light in the wavelength range can be selectively absorbed. For example, the first photoelectric conversion element 100a may be a red photoelectric conversion element. The second electrode 20a may be a light receiving electrode, and the first electrode 10a may be connected to the charge storage 55a.

An intermediate insulating layer 65 is formed on the first photoelectric conversion element 100a.

The second photoelectric conversion element 100b is formed on the intermediate insulating layer 65.

The second photoelectric conversion element 100b includes a first electrode 10b and a second electrode 20b facing each other, a photoelectric conversion layer 30b positioned between the first electrode 10b and the second electrode 20b, And it includes an inorganic nano-layer (40b). The first electrode 10b, the second electrode 20b, the photoelectric conversion layer 30b, and the inorganic nano layer 40b are as described above, and the photoelectric conversion layer 30b is one of red, blue, and green. Light in the wavelength range can be selectively absorbed. For example, the second photoelectric conversion element 100b may be a blue photoelectric conversion element. The second electrode 20b may be a light receiving electrode and the first electrode 10b may be connected to the charge storage 55b.

The upper insulating layer 80 is formed on the second photoelectric conversion element 100b. The lower insulating layer 60, the intermediate insulating layer 65, and the upper insulating layer 80 have a plurality of trenches exposing the charge storages 55a, 55b, 55c.

The third photoelectric conversion element 100c is formed on the upper insulating layer 80. The third photoelectric conversion element 100c includes a photoelectric conversion layer 30c positioned between the first electrode 10c and the second electrode 20c, the first electrode 10c and the second electrode 20c facing each other, And includes an inorganic nano-layer (40c). The first electrode 10c, the second electrode 20c, the photoelectric conversion layer 30c, and the inorganic nano layer 40c are as described above, and the photoelectric conversion layer 30c is one of red, blue, and green. Light in the wavelength range can be selectively absorbed. For example, the third photoelectric conversion element 100c may be a green photoelectric conversion element, and the aforementioned photoelectric conversion element 100 may be applied. The second electrode 20c may be a light receiving electrode, and the first electrode 10c may be connected to the charge storage 55c.

A condenser lens (not shown) may be further formed on the third photoelectric conversion element 100c. The condenser lens can control the direction of incident light to collect light into a single point. The condenser lens may be, for example, a cylinder shape or a hemisphere shape, but is not limited thereto.

In the drawing, the first photoelectric conversion element 100a, the second photoelectric conversion element 100b, and the third photoelectric conversion element 100c are illustrated by way of example, but the photoelectric conversion element 100 of FIG. 1 is illustrated. The photoelectric conversion element 200 may be applied in the same way.

In the drawing, a structure in which the first photoelectric conversion element 100a, the second photoelectric conversion element 100b, and the third photoelectric conversion element 100c are sequentially stacked is not limited thereto, and the stacking order may be variously changed.

As described above, the first photoelectric conversion element 100a, the second photoelectric conversion element 100b, and the third photoelectric conversion element 100c that absorb light in different wavelength regions have a stacked structure, thereby increasing the size of the image sensor. Further reduction in size can be achieved.

12 is a cross-sectional view illustrating another example of the organic CMOS image sensor of FIG. 10.

Referring to FIG. 12, the image sensor 1000 according to the present exemplary embodiment includes a semiconductor substrate 110, a lower insulating layer 60, an intermediate insulating layer 65, and an upper insulating layer 80, as in the above-described embodiment. It includes a first photoelectric conversion element (100a), a second photoelectric conversion element (100b) and a third photoelectric conversion element (100c). However, unlike the above-described embodiment, the positions of the first electrode 10 and the second electrode 20 of the first photoelectric conversion element 100a, the second photoelectric conversion element 100b, and the third photoelectric conversion element 100c Is changed. That is, the first electrodes 10a, 10b, and 10c may be light-receiving electrodes, and the second electrodes 20a, 20b, and 20c may be connected to charge storages 55a, 55b, and 55c.

13 is a plan view schematically showing an organic CMOS image sensor according to an embodiment, and FIG. 14 is a cross-sectional view showing an example of the organic CMOS image sensor of FIG. 13.

13 and 14, the organic CMOS image sensor 1100 includes a photoelectric conversion element 90 positioned on the semiconductor substrate 110, and the photoelectric conversion element 90 includes a plurality of photoelectric conversion elements 90- 1, 90-2, 90-3). The plurality of photoelectric conversion elements 90-1, 90-2 and 90-3 may convert light (eg, blue light, green light or red light) of different wavelength regions into electrical signals. Referring to FIG. 14, a plurality of photoelectric conversion elements 90-1, 90-2, and 90-3 are arranged side by side on the semiconductor substrate 110 in a horizontal direction and parallel to the surface 110a of the semiconductor substrate 110. Partially or totally overlapped with each other in the extended direction. Each photoelectric conversion element (90-1, 90-2, 90-3) is connected to a charge storage (55) integrated in the semiconductor substrate (110) through a trench (85).

Each photoelectric conversion element 90-1, 90-2, 90-3 may be one of the photoelectric conversion elements 100 and 200 described above. In one example, two or more photoelectric conversion elements 90-1, 90-2, 90-3 are different from the common continuous layer that extends continuously between the photoelectric conversion elements 90-1, 90-2, 90-3. It can include parts. For example, the plurality of photoelectric conversion elements 90-1, 90-2, and 90-3 may share the common first electrode 10 and / or the common second electrode 20. For example, two or more photoelectric conversion elements 90-2, 90-2, and 90-3 may have different photoelectric conversion layers 30 capable of absorbing light in different wavelength regions of incident light. For example, two or more photoelectric conversion elements 90-1, 90-2, and 90-3 may include inorganic nanolayers 40 of different configurations. Other structures of the organic CMOS image sensor 1100 may be the same as one or more of the organic CMOS images described with reference to FIGS. 3 to 12.

15 is a cross-sectional view showing an example of an organic CMOS image sensor.

Referring to FIG. 15, the organic CMOS image sensor 1200 includes a semiconductor substrate 110 and photoelectric conversion elements 90-1 and 91 stacked on the semiconductor substrate 110. The photoelectric conversion element 91 includes a plurality of photoelectric conversion elements 90-2 and 90-3, and the plurality of photoelectric conversion elements 90-2 and 90-3 have a surface 110a of the semiconductor substrate 110. It can be arranged to overlap in a direction extending in parallel. The plurality of photoelectric conversion elements 90-1, 90-2 and 90-3 may photoelectrically convert light (eg, blue light, green light, or red light) having different wavelengths into electrical signals.

As an example, the photoelectric conversion element 90-1 may include a plurality of horizontally arranged photoelectric conversion elements capable of absorbing light in different wavelength regions. As an example, the photoelectric conversion element 91 may photoelectrically convert light in one wavelength region selected from blue light, green light, and red light. As an example, the photoelectric conversion element 91 may be wholly or partially overlapped with the photoelectric conversion element 90-1. Other structures of the organic CMOS image sensor 1200 may be the same as one or more of the organic CMOS images described with reference to FIGS. 3 to 12.

16 is a cross-sectional view showing an example of an organic CMOS image sensor.

Referring to FIG. 16, the organic CMOS image sensor 1300 includes a semiconductor substrate 110 on which photosensitive elements 50a and 50b, a transfer transistor (not shown), and a charge storage 55 are integrated; An upper insulating layer 80 and a color filter layer 70 positioned on the semiconductor substrate 110; And a lower insulating layer 60 and a photoelectric conversion element 90 positioned under the semiconductor substrate 110. The photoelectric conversion elements 90 may be the photoelectric conversion elements 100 and 200 described above. In FIG. 16, the photoelectric conversion element 90 is positioned below the semiconductor substrate 110 so that the photoelectric conversion element 90 and the color filter layer 70 are separated from the photosensitive elements 50a and 50b. . Other structures of the organic CMOS image sensor 1300 may be the same as one or more of the organic CMOS images described with reference to FIGS. 3 to 12.

The above-described photoelectric conversion element and the organic sensor including the image sensor may be applied to various electronic devices, for example, a mobile phone, a digital camera, but are not limited thereto.

17 is a schematic diagram of an electronic device according to an embodiment.

Referring to FIG. 17, the electronic device 1700 may include a processor 1720 electrically connected to each other through a bus 1710, a memory 1730, and an organic CMOS image sensor 1740. The organic CMOS image sensor 1740 may be any one according to the above-described implementation. Memory 1730, which is a non-transitory computer-readable medium, may store an instruction program. The processor 1720 may execute a stored instruction program to perform one or more functions. As an example, the processor 1720 may process an electrical signal generated by the organic CMOS image sensor 1740. Processor 1720 may generate output (eg, an image to be displayed on the display interface) based on such processing.

Hereinafter, the above-described embodiment will be described in more detail through examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of rights.

Example 1

ITO is sputtered on the glass substrate to form an anode of 150 nm thickness. Subsequently, a compound represented by the following Chemical Formula A is deposited on the anode to form a charge assist layer having a thickness of 5 nm. Subsequently, a p-type semiconductor represented by the following Chemical Formula B-1 (λ _max : 545 nm) and an n-type semiconductor fullerene (C60) are co-deposited in a 1: 1 volume ratio on the charge auxiliary layer to form a 100 nm thick photoelectric conversion layer. Then, Yb (WF: 2.6 eV) is thermally deposited on the photoelectric conversion layer to form an inorganic nano layer having a thickness of 1.5 nm. Subsequently, ITO (WF: 4.7 eV) was sputtered on the inorganic nano layer to form a 7 nm thick cathode. Subsequently, aluminum oxide (Al ₂ O ₃ ) is deposited on the cathode to form an antireflection layer having a thickness of 50 nm and sealed with a glass plate to manufacture a photoelectric conversion element.

[Formula A]

[Formula B-1]

Comparative Example 1

A photoelectric conversion device was manufactured in the same manner as in Example 1, except that the inorganic nano layer was not formed.

Example 2

A photoelectric conversion device was manufactured in the same manner as in Example 1, except that a 90-nm-thick photoelectric conversion layer was formed by co-depositing the p-type semiconductor and the n-type semiconductor at a volume ratio of 1.2: 1.

Comparative Example 2

A photoelectric conversion device was manufactured in the same manner as in Example 2, except that the inorganic nano layer was not formed.

Example 3

A photoelectric conversion device was manufactured in the same manner as in Example 1, except that a p-type semiconductor and an n-type semiconductor were co-deposited at a volume ratio of 2.5: 1 to form an 80nm-thick photoelectric conversion layer.

Comparative Example 3

A photoelectric conversion device was manufactured in the same manner as in Example 3, except that the inorganic nano layer was not formed.

Evaluation I

The characteristics of residual electrons of the photoelectric conversion elements according to Examples and Comparative Examples are evaluated.

Residual electronic property refers to the amount of charge in which the photoelectrically converted charge in one frame remains unused for signal processing and the charge of the previous frame is read in the next frame, and the photoelectric conversion element according to Examples and Comparative Examples The light in the wavelength region where photoelectric conversion can occur is irradiated for a certain period of time, and the light is turned off and evaluated from the amount of current measured in units of 10 ^-6 seconds with Keithley 2400 equipment.

The results are shown in Tables 1 to 3.

Residual electron (e ^-) 30 fps 240 fps 960 fps Example 1 1.3 ± 0.1 10.3 ± 1.0 18.0 ± 1.8 Comparative Example 1 2.6 ± 0.2 17.2 ± 2.0 36.1 ± 1.8

Residual electron (e ^-) 30 fps 240 fps 960 fps Example 2 2.7 ± 0.1 17.0 ± 1.2 40.2 ± 1.5 Comparative Example 2 3.5 ± 0.2 19.9 ± 2.3 51.9 ± 4.5

Residual electron (e ^-) 30 fps 240 fps 960 fps Example 3 13.7 ± 0.2 104.8 ± 1.7 251.1 ± 3.3 Comparative Example 3 26.4 ± 1.4 167.6 ± 2.1 356.9 ± 5.3

Referring to Tables 1 to 3, it can be seen that the photoelectric conversion device according to the embodiment including the inorganic nano layer has improved residual electronic properties compared to the photoelectric conversion device according to the comparative example not including the inorganic nano layer.

Evaluation II

The photoelectric conversion efficiency of the photoelectric conversion elements according to Examples and Comparative Examples is evaluated.

The photoelectric conversion efficiency (EQE) is evaluated by the Incident Photon to Current Efficiency (IPCE) method in the wavelength range of 400 nm to 720 nm.

The results are shown in Tables 4 and 5.

Photoelectric conversion efficiency (EQE,%) Example 1 72.3 Comparative Example 1 70.7

Photoelectric conversion efficiency (EQE,%) Example 3 61.3 Comparative Example 3 60.0

Referring to Tables 4 and 5, it can be seen that the photoelectric conversion elements according to the embodiments exhibit equivalent or improved photoelectric conversion efficiency compared to the photoelectric conversion elements according to the comparative example.

Evaluation III

An organic CMOS image sensor to which a photoelectric conversion element according to Examples and Comparative Examples was applied was designed, and YSNR10 of the organic CMOS image sensor was evaluated.

YSNR10 of the organic CMOS image sensor is the illuminance (unit: lux) where the ratio of signal and noise (signal / noise) is 10, where the signal is the RGB raw signal (RGB raw) calculated by the FDTD (finite difference time domain method) signal) is the sensitivity of a signal obtained through a color correction step through a color correction matrix (CCM), and noise is noise generated when measuring a signal in an organic CMOS image sensor. The color correction step is a process of reducing the difference from the actual color by performing image processing on the RGB raw signal obtained from the organic CMOS image sensor. The smaller the YSNR10 value, the better the image characteristics at low illumination.

Table 6 shows the results.

YSNR10 Example 1 84 Comparative Example 1 87

Referring to Table 6, the photoelectric conversion element according to the embodiment can be confirmed that the YSNR10 is lowered compared to the photoelectric conversion element according to the comparative example, from which it can be expected that the sensitivity of the organic CMOS image sensor can be improved. have.

Although the embodiments have been described in detail above, the scope of rights is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts defined in the following claims also belong to the scope of rights.

10, 10a, 10b, 10c: first electrode
20, 20a, 20b, 20c: second electrode
30, 30a, 30b, 30c: photoelectric conversion layer
40, 40a, 40b, 40c: inorganic nano layer
45: charge auxiliary layer
50a, 50b, 50c: light sensing element
60: lower insulating film 70: color filter layer
80: upper insulating film 85: trench
100, 200: photoelectric conversion element
300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300: image sensor
1700: electronic devices

Claims (22)

The first electrode and the second electrode facing each other,
A photoelectric conversion layer positioned between the first electrode and the second electrode and absorbing light in at least a portion of a wavelength region to convert it into an electrical signal, and
An inorganic nano layer located between the first electrode and the photoelectric conversion layer and comprising a lanthanide element, calcium (Ca), potassium (K), aluminum (Al), or an alloy thereof
Photoelectric conversion element comprising a.
In claim 1,
The lanthanide element is a photoelectric conversion element comprising ytterbium (Yb).
In claim 1,
The inorganic nano-layer is a photoelectric conversion element in contact with the first electrode.
In claim 1,
One surface of the inorganic nano-layer is in contact with the first electrode,
The other side of the inorganic nano layer is in contact with the photoelectric conversion layer
Photoelectric conversion element.
In claim 1,
The first electrode is a photoelectric conversion element that is a transparent electrode having a light transmittance of 80% or more or a reflective electrode having a light transmittance of less than 10%.
In claim 5,
The transparent electrode is a photoelectric conversion device comprising at least one of an oxide conductor and a carbon conductor.
In claim 1,
The thickness of the inorganic nano layer is 5nm or less photoelectric conversion device.
In claim 1,
The thickness of the inorganic nano layer is 2nm or less photoelectric conversion device.
In claim 1,
The first electrode is a cathode and the second electrode is an anode.
A first electrode comprising a transparent conductor having a light transmittance of 80% or more or a reflective conductor having a light transmittance of less than 10%,
A photoelectric conversion layer located on the first electrode and absorbing light in at least a portion of a wavelength region to convert it into an electrical signal, and
A second electrode positioned on the photoelectric conversion layer
Including,
The surface of the first electrode facing the photoelectric conversion layer is covered with an inorganic nano layer having a thickness of 5 nm or less,
An effective work function at the surface of the first electrode facing the photoelectric conversion layer is smaller than the work function of the transparent conductor or the reflective conductor.
In claim 10,
The difference between the work function of the transparent conductor or the reflective conductor and the effective work function on the surface of the first electrode facing the photoelectric conversion layer is 0.5 eV or more.
In claim 10,
The work function of the transparent conductor or the reflective conductor is 4.5 eV or more,
The photoelectric conversion element having an effective work function at the surface of the first electrode facing the photoelectric conversion layer is 4.0 eV or less.
In claim 12,
The photoelectric conversion element having an effective work function at a surface of the first electrode facing the photoelectric conversion layer is 3.0 eV or less.
In claim 10,
The inorganic nano-layer includes an inorganic material,
The inorganic material is a photoelectric conversion device comprising a lanthanide element, calcium (Ca), potassium (K), aluminum (Al) or alloys thereof.
In claim 14,
The lanthanide element is a photoelectric conversion element comprising ytterbium (Yb).
In claim 10,
The transparent electrode is a photoelectric conversion element comprising an oxide conductor or a carbon conductor.
In claim 10,
The inorganic nano-layer photoelectric conversion device having a thickness of 2nm or less.
In claim 10,
The first electrode is a cathode and the second electrode is an anode.
An electronic device comprising the photoelectric conversion element according to claim 1.
An organic sensor comprising the photoelectric conversion element according to claim 1.
In claim 20,
The organic sensor is an organic CMOS image sensor.
An electronic device comprising the organic sensor according to claim 20.

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